Unfortunately i've had to get used to the BBC's random approach to scheduling MITM. They haven't really bothered trailing the show since the first season; they seem to want to treat the show as kind of cult viewing, and don't want to push it on a wider audience. One just has to accept that really, and just make sure that every week you check the schedules.
It normally starts around this time of year so from about June time i've been checking the schedules for the new series, which is why i found it (also the Guardian reviewed the double bill very favourably as it tends to when the new series starts). I did post but only on Sunday morning so sorry if you guys missed the warning.
The next trick is once you realise it's on you have to check the schedules every week, don't just assume it will be on at the same time weekly. Also, i've learnt that sporting events nearly always take precedence in the scheduling over MITM, and other shows that supposedly have a "niche" audience. For instance next week the Open Golf is on, and although it should finish before MITM is due to start you never can be sure, and if it does overrun MITM will almost definitely be shown at "a later date". Basically, you've just got to stick with it, and try to support it when it is on, despite the obstacles that the BBC seem hell bent on putting in your way!