I bought a new phone a couple weeks back and with it have started the process of changing carrier. In the interim, I have been using my old phone with my old carrier. I have already paid for the first month of the plan, however my phone number has not been transferred yet (I've told the new carrier my number, but not given the final ok yet). Today, I received the SIM card from my new carrier in the mail and put it into my new phone. On startup, I received a notification that I had 2 new texts. I opened the notification and there were two texts from 4 days ago, sent by people that I know, that I had never, and still haven't, received on my old phone. I have texted back and forth with both people since that time with all messages coming to my old phone. There was an incredibly short period where I had 0 texts left (TracFone doesn't do unlimited texting), that I believe was no longer than a hour or two and I'm pretty sure didn't line up with these two texts. How and why could this happen? I'm worried that I could have missed some other texts and a little perplexed as to how they came to my new phone with the new SIM card.
If it matters, I'm going from a Galaxy s7 to a Pixel 3a and from TracFone to Verizon.