I currently have about £17k in a Marcus account. I am due to receive roughly £35k next year from an inheritance, which is approximately 2 years worth of ISA contributions.

I have already contributed £4k to my cash LISA for this year, but the other £16k of my ISA allowance is available. Is there any reason not to transfer £16k from my Marcus account into a cash ISA? They seem to pay about the same rate and I think I can still access the cash without penalty if I need it?

Also, would I be able to easily transfer that £16k across to a S&S ISA in the future if I wanted? I am going to keep it in cash for the moment as there is a possibility I might be buying property in the short to medium term, but if I am able to buy property without using all of my cash as a deposit I would like to begin investing for the longer term.