Table of common offences: https://bit.ly/2UwYc2J
This is a handy summary in table form which shows you the common charges, whether they would be tried in a magistrates or crown court and maximum sentences. Mostly people have been given Conditional Discharges and costs of a few hundred pounds, however only small numbers have been sentenced at this point and also most have not been repeat convictions.
Understanding Laws Affecting Protestors by Netpol:
Sentencing Councils full list of offences tried in Magistrates Courts (many not protest related):
For Sentencing Councils full list of Crown Court offences, see https://www.sentencingcouncil.org.uk/crown-court/
Sentencing on Conviction by Netpol: