When can I expect my TAX refund from SIPP contribution?

I’ve contributed to a SIPP for the first time as a high rate tax payer so have completed the first pension relief form on HMRCs website to claim the additional tax.

My understanding is this refund comes back as a cheque.

Two questions:

1. When can I expect this cash refund?

2. Is it always paid as a cheque? I don’t want them to simply reduce my 2026-27 tax bill. I want my money.

Thanks.