Share identification clarification request and CGT loss offset

Hello, I have questions covering two aspects of CGT with which I hope that you can help; 1) Can I offset a loss made trading shares in one company against profits made in another? For example, if I were to make realised gains of £50,000 trading shares in company X and also, in the same tax year, make a realised loss of £20,000 in company Y, would my overall P/L of £30,000 (£50k - £20k) be the CGT figure that I should declare and would my tax liability be based on £30k, rather than £50k? 2) Regarding share identification, from the following link, https://www.gov.uk/hmrc-internal-manuals/capital-gains-manual/cg51560, it would appear that if selling shares and then buying them back within 30 days that any CGT liability would be based on the profit or loss of the initial disposal VS the later repurchase. Is there any way that it is possible to wait longer than 30 days and still match a later repurchase against a prior disposal? Ie, can I sell shares that I've owned for one year on 1st May, buy them back on 1st August and be taxed on the P/L on the sale of 1st May vs purchase on 1st August rather than the initial purchase and initial disposal? 3) Following on from the above, are ALL purchases within 30 days of a disposal matched against that disposal, regardless of P/L and dates on which the disposal and repurchase took place? Many thanks in advance.

Hi,
You can set the loss from one asset against the gain of another in the same tax year.  This would be visible in the evidence provided when declaring the gain.
If the loss is declared in a previous tax year it can be carried forward and set against the gain, again supported by evidence when declaaring the gain. The rule is 30 days and no more.  
Have a look at:
CG13370
Thank you.