GWH - if the delay is less than 20 mins you do not get an EAT.
At TC, Heathrow and Gatwick traffic managers will often put up individual delay times if it is getting near to 20 mins (i.e. 14, 15 minutes) and I for one always tell A/C "your delay is ... mins"
HOWEVER - it is not a requirement on the traffic managers behalf.... it is more to give me, the Area controller an idea of delays and it usually means that they are on the increase i.e. it's a warning to me that EATS may well soon come in force for the next lot of arrivals.
My only obligation to the A/C would be to say "delay is less than 20 mins" if I really felt pedantic.
Alibaba - being told that an A/C can only hold 1 and a half more times is what I would consider a late call.
A/C surely know that they are destined to a busy airfield. 20 minutes holding should be expected, anything less is a bonus. It sounds like this particular A/C did not have the fuel to do that. That in my book amounts to bad airmanship!!