How long does it take to upgrade a mast?

[wishawpubs]

Just over a month ago the mast which is closest to my home went offline. According to Three's service status page upgrades were being performed. 

Following the first week the status page had reverted back to being no issues, however last week there was an issue being investigated with this week reverting back to no issues.

I had been getting speed of 70Mb up and 40Mb down. But now only getting around 20Mb down and 8Mb up on a good day. 

Is there anyway of checking how long the mast will be out of action?

Below is photo of men working at the top of the mast a month ago.

[wishawpubs]

Up until last week 4G home broadband was being offered. This week it doesn't seem to be available. 

[wishawpubs]

I've had much the same experience. Jumping from H+, 4G, 4G+ and a hint of 5G if the wind blows in the right direction.  

[sc1999]

According to the network status checker they have been working on my mast for 8 weeks and my service runs from 3g, h, h+, 4g and the occasional flicker of 5g. Calling 333 was of no help.