Ouch! Looks like you fell foul of the dreaded early-morning-spread factor, Nemesis.
Before the offer price dropped to 67p this morning, it was briefly at 70p, and before about 8:45am it was at a whopping 81.5p for at least the previous 15 minutes (not sure about earlier than that but should be able to check today's history in greater detail this evening if needed).
I'm going by the intraday chart at advfn.com. The trades listing won't show this because nobody out there appears to have traded before 8:52am, by when the initial high spread had disappeared. They may well have deliberately been avoiding the early spread.
Worth clarifing with Sharky whether overnight trades are meant to be dealt at 9am (safely clear of most big morning spreads) or just recorded at 9am but dealt 20 minutes sooner - in which case falling into the expensive territory on KCOM this morning.
(I'm not sure if this facility is available on the free access version? Maybe it is. The chart is the one you get when left-clicking (to enlarge) the right-hand chart on the 'quote' page.. or just go via the 'intraday' tab on the menu bar and select same shaded-spread setting).
PS:If this doesn't work for you I can email you a copy of the chart via the link in your profile (assuming T2W's emailing setup will accept the picture. If not, email me and I'll email you direct).