Traveling to London’s Heathrow Airport by chance early next month?

Check those flight arrangements.

For the third time in six weeks, the Unite union for Mixed fleet cabin crew workers for British Airways will stage a walkout strike as it continues to fight for a wage increase from the airline.

Mixed fleet are cabin crew workers who can be assigned to any type of flight out of Heathrow – short domestic hops, flights to other European cities, or long-haul flights to the U.S. and other destinations. BA’s departures from Gatwick, London City and Stansted airports are unaffected.

Twice in January the cabin crew walked out, once for two days and another time for three days, forcing BA to cancel a total of 68 flights.

This time, the union plans to strike twice for a total of six days in early February – Feb. 5, 6 and 7, with a return to work on the 8th, and then again Feb. 9, 10 and 11. British Airways previously was able to keep the disruptions to a minimum by chartering in other aircraft and crew.

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In a letter sent to British Airways this, Unite officials wrote: "Your reluctance to offer a reasonable pay deal to our members, yet spend what we believe is now reaching millions of pounds in trying to quash strike action, suggests money is available and this is a question of ideology. Rather than addressing poverty pay, British Airways is spending money hand over fist on chartering in aircraft to cover striking cabin crew. If it can afford to waste money in such a manner then British Airways can clearly afford to address pay levels which are among the lowest in the industry.”

In a statement, BA quickly fired back.

“We will publish more details on Tuesday (Jan. 31) once we have finalized our contingency plans in relation to the strikes called for 5-7 February. On Thursday we will publish more details in relation to the second strike period, 9-11 February. Our pay offer for mixed fleet crew is consistent with deals agreed (to) with Unite for other British Airways colleagues. It also reflects pay awards given by other companies in the UK and will ensure that rewards for mixed fleet remain in line with those for cabin crew at our airline competitors."