Where did you see this? Sources are saying that Hezbollah recently upgraded their pagers with the American University of Beirut on August 29:
https://x.com/gazanotice/status/1836082218805891360
Why would Israel have the ability to wipe out a good chunk of Hezbollah for years and just sat on it until now?
They are claiming 2750 injuries:
https://www.aljazeera.com/news/2024/9/17/dozens-of-hezbollah...
Please do not conflate Hezbollah and AUB.
The claim is that AUB medical school pagers were replaced a week or so ago. This is either pure coincidence, false or fake news to imply that AUB has Israeli operatives, or indeed that the pagers used were compromised and that the USA was aware of the impending attack and did not want to harm AUB medical staff - who probably are mostly not connected with Hezbollah.
Further reading: https://x.com/AUBMC_Official/status/1836086847153320148
So no data exfiltration was possible using the pagers. The only purpose of the modified pagers was to maim or kill their possessors, by detonating all of them simultaneously.
It's how the TV detectors work in countries, such as the UK, that charge a license fee for TVs.
Military radios can't use this common technique because of the risk of detection.
I suspect pagers only receive on 1 or at most a few frequencies. If that's correct, they wouldn't need that technique.