The office phoned him and then called me back to advise me that he was going to come back later in the day, which he did and when he came he claimed that he had the wrong address in the first instance and appolgised. He replaced the RCD and MCB and then replaced the inverter, by which time the daylight had gone so he was unable to get the panels generating any DC in order to initialise the inverter and that he would have to come back again to do it or I could do it, I said that I was not going to touch it (thinking that if it didn't work, they might use that as an excuse not to fix it) so he had to arrange to back again the following Tuesday, the 28th.
He was also supposed to tidy up the rough installation that the installers left behind, which he didn't so I phoned the office and requested that when he came back, he did that as well.
This Tuesday, he came back and got the inverter working, and replaced the 25mm2 tails to the RCD (incoming cable from inverter is only 6mm2) with new 15mm2, the crap distribution board for the RCD and MCB and place the tails in trunking.
This he did, but did not remove the Henley Block to the intake cupboard, so we still have this in full view above the front

The only other item they could have replaced was the panels themselves, where has all the skilled people gone? By replacing so much, they are bound to find the faulty part, aren't they?
So now we have had a new inverter installed, and the RCD and MCB have been replaced twice, last Tuesday and this Tuesday (why) and a new metal enclosure for the RCD and MCB along with new 15mm2 tails but the fugly Henley Block remains, he never had enough tails he claimed.
So I'll have to replace the trunking, or at least the lid myself, good job my middle son works at an electrical wholesaler so he can get hopefully a piece of damaged trunking for it.
This has only taken since July 7th 2022 to get resolved, does no-one care about service any more?
The photo shows the old tails and Henley Block, the old fixing holes etc are the result of the consumer being replaced earlier to provide some extra MCB ways for new circuits.