Your mast upgrade spoiled my connection!

[Rob64]

I got the Three broadband box a couple of weeks ago to evaluate as my possible primary broadband source.

It looked promising, although I am on the edge of the indoor coverage zone, I worked out where the lone mast was and by putting the router on a little shelf high in the loft eve facing the mast I got a rock steady 'good' 5G signal. Speeds were typically 50 to 100mb, off peak even hitting 180mb at times, other times dropping down to 30mb for short periods. I even ordered an 4x4 MIMO external antenna with a view to mount externally on a pole for more height (height is always good in radio)

Then a few days ago 5G disappeared, the service status page said they were doing mast upgrades to be finished on the 16th. I was looking forward to probably even stronger service.
Its come back on and the workmen have gone, but its really poor!!  With the router in the same position I can only get 'fair' signal, I have spent a lot of time tweaking the position around but cannot get it to improve. Sporadically it flips to 'good' with a sub -100db signal but signal quality -12db is poorer and it quickly flips back to the weaker channel -108db with better quality -3db. I can't get past 20 to 35mb and before it was pretty stable but now the speed wobbles like crazy.

I am really gutted, I was gearing up to cancel my cable broadband and switch to the far better value Three 5G, but its now looking like I will be sending the router back, luckily I only took the 1 month at a time deal.
They have done what ever they did to the mast (big tower - 3 guys up it for days) and gone so its not likely its going to improve is it? and my area (small town) is unlikely to get another 5G mast anytime soon.

[Rob64]

Hi, Thanks for the info. I have posted subsequently about how the coverage map had changed quite a lot recently, the 'reach' of the mast being some what reduced so where as before I was just in the 'inside/outside' Red zone, its now falls quite a bit short of my location and the map has been revised since the works.
I don't think I am mast switching because they are very rare around here with 5G and I am definitely staying locked on 5G, the one above is the only Three 5G for some distance around here, in any other direction there is virtually no 5G I could pick up, the corner of the loft facing out to this mast is the only place I get any coverage.
Something a bit disconcerting is the difference loading on the mast makes, a speed tests at the crack of dawn today saw an amazing over 200mb, tested at peak midday a mere 25mb, just tested now 6pm, 82mb and monitoring over a lot of days this pattern is not unusual. It tends to be a bit all over the place.

Its just a pity the locations of the masts carrying Three and which services - or the upgrade schedule is not published. I have a collection of masts virtually at the top of my road that had a lot of work a while ago but from the coverage map its not got Three on them otherwise I would have more signal strength than I could imagine!