RC061543819MY is Malaysia Post parcel, destination is USA. Some China seller use Malaysia Post to ship battery item. The parcel will go to Malaysia first , then to other country(in your case, USA).

Normally parcel will travel about 2 to 4 weeks from Malaysia to USA. If it fails delivery, it can not be returned to China. Normally Malaysia will discard such undeliverable parcel.

Quote from kecola81 on October 8, 2015, 23:33
Hi! My tracking number is RC061543819MY. I'm tracking my package by an app called trackchecker because it's way more detailed. Here's where the tracking gets weird and confusing.

9/24/2015 11:05 AM - Origin Post is Preparing Shipment

9/24/2015 3:04 PM - Your item has been processed to ISC LOS ANGELES CA (USPS) BUTTERWORTH

9/24/2015 3:04 PM - Item sent to ISC LOS ANGELES CA (USPS) BUTTERWORTH

9/25/2015 - Origin Post is Preparing Shipment

9/26/2015 - Origin Post is Preparing Shipment

Everyday since then I get the same status update 'origin post is preparing shipment'. Why did tracking say that my package had reached the US (Los Angeles) and then go back to saying origin post is preparing shipment? ...

Further to which -- that is really weird, it looks like the trackchecker app is pulling updates from both POS Malaysia and the USPS, then mashing them together into one. That's going to give really bizarre results, as you're seeing.

Probably the core of the matter is that the USPS likes to post the status "Origin post is preparing shipment" from the time they get electronic notification that the parcel is coming until they actually physically receive it.

The items above mentioning the ISC (Int'l Svc Center) in Los Angeles are from POS Malaysia saying that your item has just been sent there, not received there yet.

If you're curious, you can compare the two tracking sources on their respective websites:

http://www.pos.com.my/postal-services/quick-access/?track-trace#trackingIds=RC061543819MY

http://tools.usps.com/go/TrackConfirmAction?qtc_tLabels1=RC061543819MY

Quote from kecola81 on October 15, 2015, 03:35
Shadowspar, thank you for your reply! You can see how this can be confusing. I keep telling myself that isc los angeles showed up in the tracking because Malaysia Post has somehow input info showing that that is where my package will be sent. It's hard not to worry though because of the order of the tracking events.

You're welcome! It is definitely confusing. I truly wish postal operators the world over were more transparent about how the mail handling process works, so that people didn't have to worry so much.

To expand a little bit, the USPS has five offices of exchange for international mail: Los Angeles, San Francisco, Chicago, Miami, New York. To send mail to the US, the originating postal service has to deliver it to one of these five offices. From there, the USPS assumes custody of the mailpieces and delivers them domestically. Items from the Asia-Pacific region are almost always routed to LA or SF, and the message from POS Malaysia is just confirming that your item is bound for Los Angeles.

One other thing: after they are handed off to the airline for transport, items usually appear to "freeze" at their last location in the originating country; they won't be updated again until they reach the destination country and are scanned there. Parcels may transit many countries enroute to the destination, and they are usually packed into sealed mailbags for transit, so nobody in between could scan them even if they wanted to. These three FAQs have more info on what's going on during that time period:

How long will China Post parcel arrive my country? How long will my tracking status be updated?

I can fly to China in 24 hours! Why does a package take weeks?

How does the international mail system work? How is mail routed from one country to another?

For the past 21 days, the status has been stuck at origin post is preparing shipment and it's a big order too

Yup. Again, it'll say that from the time the USPS receives electronic notification that the item is coming, until they actually receive and scan it.

Actually, one more thing: it might continue to say that until it arrives at your door. Starting October 1st, the USPS doesn't post tracking information online for most incoming Registered Mail items. Unfortunately, this is part of a bigger international catfight between postal operators over how much postal services get compensated for delivering inbound international mail.

China Post Forum

It has 17 days to reach me before buyer protection from aliexpress reaches me so I'm hoping it comes soon.

If the end of your buyer protection period is nearing and the shipment still hasn't arrived, most good sellers will be happy to extend it for you.

Best wishes for speedy arrival of your shipment. =)