GPy Modem Firmware 48829 problems attaching

[EL45]

Hello,
I am running into problems with SIM cards after performing modem updates. Here is the different results I am getting with the same hardware, software and SIM cards, with different modem versions.

LR5.1.1.0-47510 (came stock on this GPY)
Verizon, Telnyx and Hologram sims all working fine

LR5.1.1.0-41065
Verizon and Hologram sims work. Telnyx won't attach

LR5.2.1.0-48829
Verizon only works. Telnyx and Hologram won't attach

Below are the differences in the code for the different SIM providers.
Verizon

lte = LTE(carrier='verizon')
lte.init(carrier='verizon')
lte.attach()

Hologram

lte = LTE()
lte.init()
lte.attach(apn='hologram')

Telnyx

lte = LTE()
lte.init()
lte.attach(apn='data00.telnyx')

Can anyone provide any insight on what has changed in the different modem versions and how I could get things working again on newer modem versions?