Hi OP, yes you can sign up for a new lease now. Given current chip shortages in the cars, amidst other global factors, there are some pretty long lead times for a lot of cars. If you were to go for a VW ID3 this time around, for example, I think they are quoting minimum of 6 months and in some cases this is up to 12 months and more! So, not to panic you, but I'd say it's worth looking now to secure a lease for July.
There are 3 places I go to when looking: LeaseLoco, Leasing.Com, and the Pistonheads Best Leasing Deals Thread.
Best of luck!
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