More info and comment from Pitpass.com
"A mandatory limit of 18 laps of total tyre life per set will be imposed.
The life of already used tyres will be taken into consideration.
The FIA and Pirelli will communicate to the teams the remaining available laps for each set of used tyres at their disposal for the race and the criteria used to calculate that number.
There is no direct mandate for at least three tyre-change pitstops during the race, however this will be a consequence of the above guidelines should the race run its entire race distance.
Any car deemed to have exceeded the tyre life lap limit will be reported to the Stewards as being run in an unsafe condition.
This information will be formally communicated to the teams in the Race Directors’ notes and further updates issued as required."
Pitpass added:
"Even those with no concept of arithmetic will appreciate that three times 18 is 54, whereas today's race is 57 laps.
Furthermore, as if the situation wasn't bad enough, in terms of used tyres the teams are allowed to add 2 more laps to the (18) count to accommodate slower in-laps and out-laps.
Consequently, if a tyre was used for 5 laps in practice or qualifying teams would feasibly be allowed to use it for a further 15 laps.
As the FIA's communication states, the teams will be told the remaining available laps for each set of used tyres they have and the criteria used to come to that figure.
However, based on the track limits fiasco, especially after Friday's qualifying session, one fears as to the capability to give out such information under the intense pressure of a race."
