Learn about flies

From Witt's End, Bedfordshire on 4 July 2022, is this Nephrotoma cornicina please?  

From Harrold-Odell Country Park in Bedfordshire on 29 June 2022, is this Tipula oleracea please?

Is this Nephrotoma flavescens please?  Bedfordshire.  13 June 2022.   

Assuming this to be Episyrphus balteatus, I'm intrigued by the pair of red lines on its abdomen. This is the first instance of this that I've seen. Does anyone else have knowledge of this?

(Worthing's Heene Cemetery, 14th June 2022.)

Keying from Alan Stubb's British Craneflies I get this to a choice of Phylidorea ferruginea or P. longicornis. Seems to have a mix of the supposedly differentiating characters. Vein Rs is short like the plate for P. ferruginea and wing quite long. Also top of head grey dusted. But femora with strong black apical ring and suggestion of infuscation around base of Rs and crossveins, more like P. longicornis.   Beds marsh.

Can anyone please identify this long-legged fly?  Has me stumped!  5mm long, caught in native woodland by river in northern Devon on 14 May.

Is this Hydrotaea diabolus please? Beds alder woodland.