right time to take profit from an isa

I don't understand how you'd plan to "take the profit and buy more shares in the same isa,thus having more of a dividend/income payout with the extra shares" - what extra shares? If you sell and then buy back in then you're just back to square one, same shares, same income, or are you talking about being out of the market for a sustained period?

Much depends on what your objectives are - the usual recommendation on here is to invest according to objectives and risk tolerance, etc, rather than trying to time the market and trade. Given that we've been on a bull run for many years, there have been many times when people could have assumed we'd reached the high point and tried to time a sale, but of course anyone selling, say, three years ago, would have lost out on three more years of growth.

So, my view would be to stick with what you have unless it's fallen out of balance or has become misaligned with your target allocation and objectives. Or to put it another way, if you sold, what would you do with the money and how are you convinced that this would be better than leaving it where it currently is?