Pom, I’ve read about your successful activities on 4m.
However I wasn’t on a SOTA summit, but on a local p<150m peak using my SOTA setup (well, some kind of).
Guess, what signals were in the band! I heard OZ7IGY, some EI beacon (that I could not identify due to my miserable cw skills), and FT-8 signals (sic!). Not a single phone or cw signal except the beacons. CQing didn’t change this.
When the band came alive, it was only OIRT FM-W stations splattering across the entire band making any qso impossible. This opening luckily ended shortly before 1900z.
Then, within a minute, when the UKAC started, the band was crowded again, this time with strong SSB and cw signals. Good to know that you can rely on the UKAC stations even on 4m. I worked an EI and a MM station and then started CQing which resulted in a pile-up from the northern UK.
I think you’ve made peace with your IC-705 by now, haven’t you?
The IC-705 is so much fun to operate in the field and she’s a lovely radio having a wonderful RX, however with some disadvantages, e.g. a mic that is prone to wind noise. A TRX designed for outdoor operation and the mic picks up the lightest breeze… 
The reason for the first impression of the bad VHF RX was caused by a local digipeater with a poor LO spreading extraordinary noise level across the entire 2m band. This certainly resulted the IC-705 to overflow.
Anyway, maybe I will be posting my overall positive experience with the IC-705 in another thread.You just gotta love her.
I used the IC-7300 since she is the only TRX capable of 4m I have at the JO50 QTH. When packing the rucksack, I found out that the handmic was still in the JO42 shack. So I had to use the SM-30 desktop microphone, which felt a bit odd on a hilltop. 
IC-7300, SM-30 mic, 10Ah LiFePo, Delta Loop @ 4m agl.
Ahoi
Pom