Not sure if this is going to be answerable to be honest, as I'm sort of asking for a bit of retroactive mind-reading! But here goes anyway!
I was driving along Clifton Drive North, Lytham Saint Annes, England on 17/11/18 (~3:30 pm if that matters) and I saw a plane approaching the adjacent Blackpool Airport at an exceptionally low altitude (not sure on model but looked like it might have been a Cessna 400-series). It's always hard to estimate altitude accurately (particularly given I was also driving at the time) but somewhere in the order of 200-300ft at the point it crossed over the road and descending (suffice it to say I was at least half expecting a crash!)
It was highly unusual - I've lived in the area for 5+ years, and travel that road frequently (typically at least 1-2 times a day and have been using the airport for even longer) and I've never seen a plane take that approach before. Here's the aerodrome chart for BPL:
Pretty much every plane I've ever been on (either flying or being flown) has approached and landed on runway 28 - even when coming from the west (e.g. coming from IOM) the approach has always been from the SW, bearing around 50° and then turning right to about 270-280° before descending to runway 28 to land.
As far as my limited knowledge allows I believe standard altitude for approach to BPL for this is 2000ft and there is not a cat in hell's chance that this plane was anywhere near that!
I think it is possible to land on runway 10 - but that the approach path for doing that is to be coming in from the east at 1600ft bearing 256-281° and flying over before turning right to 92° and descending. The OCA for this path is 450-1000 depending on aircraft category, it's distinctly possible that the plane was at 450 (as I mention above my altitude as estimate was based off Mk 1 eyeball from a moving car so unlikely to be especially accurate!) but curiously I'm 95% certain that the aircraft didn't pass over coming from the east, I had been on the road for a good few minutes and there's nothing that would have obscured my view of them doing so - and I must admit I'd been watching the sky quite closely as I'd spent a large amount of the drive musing that conditions were fantastic and wishing I'd booked myself a lesson for that afternoon!
The plot thickens in that probably less than a minute after the plane passed over a helicopter (reasonably large - probably a offshore-rig transport) flew over on roughly the same path, but if anything even lower!
So I was wondering whether there was some circumstance causing ATC to advise a different approach from typical and what that might be?
As I mention above conditions were fantastic wind was very slight (unusually so for Blackpool at this time of year!), visibility was great - sunny with light hazy cloud that was well above (would probably have said 10,000-12,000ft +). Could operations at WRT (~6 NMi to the SSE) have had an influence?