Hi mpg,
unfortunately yes, it does include all allowances.
Base pay is 1425 GBP, allowances on the 737 per month max. an additional 225 GBP, after taxes you take home a max. of 1130 GBP.
Salary is really a joke, but it's a great company to gain quality flight time, also the 737 fleet is the best at L**da, considering working climate, nice instructor pilots, biggest route network, and so on.
Also time to command is quit short, about 4 years(starting salary for 737 CPT: ~ 3100 GBP before taxes, not including allowances), and after about 1,5 years on the 737 you may transition to the 767 or 777 fleet to get some quality heavy iron flight time in your logbook :-)
Hope that helps, always happy landings balu_777