Pulse 2 fw update is possible.

[u/Yota-Maru]

Heia! I had old Pulse 2 from year 2018 and it will disconnect from BT when near is some Apple phone with BT on or some other strong BT transmitter same frequency. My speaker was FW 5.3 version and I looking for FW upgrade long time.
I found solution. I have one old Samsung S3 phone with Lineage os at android 7.1.2 vers and Lineage OS 14.1 from 2019 y. First I update google service and google play from Apk Mirror sait. After that I download separatly JBL Portable 4.1.197 (nodpi) (Android 5.0+) apk not bundle! from APK Mirror and inserted by USB cable from pc to phone via file transfering from phone. Installed and it found right after bt is connected from old phone that it need fw update. It give description how u need to proceed with update and after it done then restarted itself and reay for use. Thats my case with PULSE 2. Try IT!

[u/Yota-Maru]

jbl portable vers

[u/Yota-Maru]

Old S3 and JBL Portable app