Found this thread on X750 band locking. I figured the modem might be taking a long time to scan through the various bands so I ran AT+QCFG="band",0,a,1 to lock the modem to band 2 and 4. No change.
I’m not 100% sure band 4 make sense, some sites suggest this is an LTE band, others suggest band 13 might be better. Lots of information about Verizon bands online but not sure which is best but I used a phonearena.com link. Would love to hear about a better source for this information. Overall the band lock did not seem to make a difference either way.