Salary for Tier 2 Extension

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I work as a Physiotherapist for NHS and I had been granted Tier 2 (General) visa (from the UK embassy in India) on the salary of £23,628. I was issued visa for 1 year initially and it is coming to it's expiry date this Mid October(2018). I am now due for an extension which my employer is happy to do. However, looking in to this forum and the Tier 2 guidance document on the Gov.uk website, suggest that I need a minimum of £30,000 salary to get an extension for Tier 2 (general).

I can also see on Tier 2 guidance document that if you are a "New entrant", a salary of £20,800 or the appropriate rate for the job is sufficient. I am currently 25 year old and in Sep 18, I will turn 26. I was wondering if I would be fine if I apply for my Tier 2 extension before my birthday in September?

Any suggestions/ideas welcome!