Returning from a temporary absence

Hi,

My client and partner intend to go abroad (outside EU) for 4-6 months.

They get PIP, irESA, CA and HB.

Do you know if their claims for: PIP, ir ESA, CA and HB will end once they have been abroad for more than the allowed time for each benefit, ie will they have to reapply for each benefit and thus claim UC instead of ESA and HB?

Or will payments simply stop being paid and then resume when they return to the UK?

I suspect that PIP and CA can resume but HB and ir ESA will not?

(I am aware of the medical treatment rules and would also be grateful for any advice on how to prove a trip is solely for medical treatment, but this question is mainly about what would happen if the trip is not deemed to be solely for medical treatment, as it seems hard to guarantee that a trip will be treated as such)

Thanks