Seeing you have a get out of jail ( contract) free card i'd leave. Join Voda on a 30 day. See how it goes, Monitor your ladies line for drops and soon as it seems stable come back and likely get a better data deal too and a new phone to do with as you please. If you wanted to come back.
I am told things should get better imminently, maybe Plymouth can double check.
I've not personally heard of a business user switching down with multi signal boxes so as i said for me an unknown but there are plenty of non business accounts with two or more signal boxes associated with them.. and as Plymouth has confirmed it's fine so no issues there.