Bus drivers have issued Government with a threat of “industrial action” not a strike notice it’s understood.Bermuda Industrial Union wrote a letter to the Ministry of Transport listing concerns over timetables earlier this month, with Minister Terry Lister claiming drivers had tabled a 21-day strike notice to end on Friday next week.Sources yesterday said in fact the letter threatens “industrial action”, as opposed to a strike, if drivers’ demands are not met.Neither the union nor the Ministry will comment on the contents of the letter, although Bus Operators and Allied Workers president Glenn Simmons has stated no strike notice has been issued.Bus drivers say proposed timetable changes would leave them with only two to four weekends off a year, instead of the 12 to 16 they currently get off.