Qantas engineers are launching targeted strikes in response to an impasse in contract negotiations, although the engineers’ union is encouraging off-duty members to offer to work overtime during the strikes.

Two-hour rolling work stoppages will begin in Melbourne on July 4, during school holidays in Australia. The Australian Licensed Aircraft Engineers Association (ALAEA) has told its members to expect more such strikes over the next few weeks if talks with the airline do not progress. Contract negotiations are due to continue this week.

The union claims in a public statement that offering to replace strikers with overtime workers, or “deliberately supplying strike-breakers against [its] own members,” is an Australian first. The ALAEA’s strategy is to convince the public that Qantas can avoid disruption if it pays overtime rates. The union believes this “places the heat fairly and squarely on Qantas’s shoulders.”

The ALAEA tells its members that the overtime offer “may seem odd but it is part of a bigger picture that will unfold over the course of the dispute. Ultimately most [members] should take part in occasional stoppages and all should be able to recover monies by working overtime at other times.”

Qantas describes the overtime ploy as a “blatantly cynical offer” that would see the company paying workers four times their normal pay while on strike. In a statement, Qantas questions what incentive the union would have to negotiate a deal if its members are earning more while striking. The airline says it is assessing contingency plans for dealing with the industrial action.