At inlaws and their infinity speed is lower than expected
is is this going to be part of the issue. This is the picture of the phone pole at the end of the driveway.
Infinity 1 is capped at 40/10 Infinity 2 is capped at 80/20. If they have Infinity 1 they are at max for that product. They would get 70 if they had Infinity 2.
Unless your in-laws habitually stream multiple HD channels or download multi GB files there would be no point in upgrading to Infinity 2
If you carry out the speedtest here and then enter their phone number and complete the further diagnostics you can tell by the upstream IP profile if they have Infinity 1 (10) or Infinity 2 (20)