Hey guys

So, with an American passport, I can spend 6 months in England with out any other visas or papers. Im trying to plan a long term trip there, but I recently came back from a long trip as well. If you guys who are familiar with the process could give some clarity, id be really apreciative.

Math incoming:

I spent roughly 4 months between June and October of 2015 in the UK.
Im currently planning 2 months from late March to May and then going again in August of 2016.

How do the dates line up? Will I be going over the allowed time or will the clock flip over before too long?

Thanks again for any help you can offer.