You might have some today. Normally all above your range:
A little bit of tropo here today.
The aircraft is flying way too low that my receiver would be able to cover it under regular conditions
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High pressure no doubt contributing to signs of Tropo this morning.
My range significantly enhanced:
I’m seeing elevation angles more negative than in flat conditions.
And graph confirms…
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I’m seeing a bit - Unusually it’s down to the south east rather than up towards Scandinavia but all tropo is good tropo 
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The tropo that’s been over Europe on VHF over the weekend seems to have finally reached 1090 MHz.
I’ve not seen a message rate like this for a long time.
Range is up as well.
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Same over here, got some tracks below the horizon into Denmark, Czechia and Switzerland, it looked like flat Earth galore 
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Picked up a C5 Galaxy over Swansea (600km from here) and saw some stationary planes at Liege Airport, 105km from my feeder!
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You both have that sharp rise at 10:00 local, i’d assume some radar interrogation settings were changed or a radar-head added?
The position rate not increasing would agree with that as position rate does not depend on interrogation.
Yes it’s quite likely to be linked to interrogation changes I think. I haven’t seen message rates that high since before the pandemic shutdown last March however. That was also with significantly more aircraft visible at the time.
I don’t know if there is a way to easily identify which radar heads are actively interrogating an aircraft, but it would be interesting to be able to see where the increased rate comes from.
Had one this morning too.
Wizz Air flying below 35.000ft but way outside my normal range:
Conditions up here this morning
I rarely see aircraft below the horizon to the East
Will be interesting to see how the latest RC software for the Airspy will perform in the current conditions.
UPDATE: The peak message rate may have passed 
However my Blue Prostick Plus receiver was seeing > 1800 messages/sec around 7:20 am (BST) . That is pretty unusual.
I got an unusually large lift this morning - I don’t normally see ducting to this extent at my location:
The direction was mostly due South, or South East with a few aircraft over Switzerland showing up.
I noticed that corresponding with the range increase was an increase of message type DF 4, which is a mode S altitude reply. I thought it a bit odd that only that single message type showed the increase:
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I’ve not checked to see if this was a genuine decode but if so, it’s a decent duct.
Things have been quite good for the last week but really picking up now.
Yes, I saw the same DF4 increase earlier today.
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That does look to be genuine - that flight was in that location at the same altitude and speed. Pretty nice range.
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Don’t think I’ve had it happen to any of my stations to this extent before… Nothing in comparison to what range you guys get… but still pretty cool…
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Very cool!
Even my receiver in the loft (so well shielded) that’s a Pi3 with a blue FA stick and a homebrew j-pole has done well today.
I have 2 identical feeders about 13.3km/7mi apart but only the second one has a clear view of the horizon due to the elevated antenne height (Jetvision A3)
When there’s some atmospheric ducting both feeders will show an increased reception range but the effect is much more pronounced for the feeder with the highest antenna.
I just wonder if this strange behaviour is common amongst those feeding from multiple locations?
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You’re also describing mine and the MTG sites. I get a lot more effect from tropo than the MTG feeder.