I didn't realise that, Being from the South East I forget that some stations don't have a service everydayRose Hill Marple has 'no Sunday service' which is absolutely correct, however by putting it at one station people may assume that all other stations on the map have a Sunday service, of course many others do not. Hyde North, Hyde Central and Woodley are examples on the same line. If this is a map about accessibility I would be tempted not to over complicate it with service levels which can easily be looked up on journey planners.
Just on a side note Westhoughton is spelt wrong but otherwise it could be a very useful resource.
Fixed Westhoughton