Cash Isa with different providers

I know there is an annual 20K limit on ISAs. I wish to focus mainly on cash this year and have invested a chunk with Provider #1. I now wish to invest another chunk into cash. Can this go into Provider #2? It will not take me over the 20K limit. Thanks.

Your new money contributions to an ISA, across all providers is 20k.

You could put 10k into A, 5k into B, and have another 5k left to go to any provider you choose.

If you then withdrew 50k from ISA C, then you you could deposit 50k into ISA C in the same tax year, and then still have 5k left.

Only if that particular ISA is flexible though, I don’t think all ISAs are necessarily flexible?