The normal thing is to try a few weeks/months and if the businessman sees a return on their investment in advertising, it is normal to continue paying the signature campaign.
You're right. The 2–3 weeks thing was also a similar situation with Roobet campaign when it debuted in 2020. Although it didn't paused at the time, anyway. Roobet has been on for two years plus now. It's likely Jambler will come back sooner than you guys even expect it.
This Campaign will initially run for 2-3 weeks before results are being evaluated to determine the future outcome.