Agree with John L above. The rules are very simple.
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per month minimum. My company pension is paid directly to SCB. I go to bank and get them to prepare a copy of all pages of my account showing the monthly deposit.(Which actually says "pension"). I get bank to produce a cover letter addressed to immigration stating that I received 12 monthly pension payments in the last 12 months. Get this letter and copy of account on day I go to immigration. Dated on the same day. This has worked every year for the past 12 years plus.