"I did wonder how the likes of Britannia, who had aircraft operating out of maybe a dozen bases around the country managed for crew basing."
The majority of Brit's pilots were Luton based, and covered the outstation work as well as LTN's own. LGW, BHX, and MAN had pilots, but not enough to cover the busy summer season. GLA and NCL had a few pilots. These bases were topped up as necessary with LTN pilots. Other unmanned bases ( BRS CWL LBA EDI LPL EMA NWI etc.) were done almost entirely by LTN pilots
The cabin crew set up was similar.
Typically, after reporting at LTN, you got positioned to wherever by taxi, or bus if there were a couple of crews, and then worked out of hotels for 3 or 4 days. Sometimes you got to or from wherever by operating part of a W pattern.
Apart from the cost of transport and hotels, this was wasteful of crew duty days, since after positioning to, say, Glasgow it was straight to the hotel ready to operate the next day, but the positioning day still counted as a duty day.
This continued until about 1991, when an attempt was made to man all the bases with the right no. of people. This was not easy,as the number of flights a base would need to operate would vary from year to year. It also meant that rounding up a crew to relieve one which was out of hours down route could be a problem. A stand-by Captain in Ltn, an F/O in Bristol, a couple of cabin crew here, a couple more there.
I left in the big redundancy of '93/4, so I don't know how well it went after that.