There is a promotion for transferring experience into free experience: 40 for 1 gold instead of 25. Such a promotion rate is quite rare – the last time was in November 2023.
The next Assembly Shop is still a long way off, but this is the best time to gain Free Experience, especially if you don’t have blueprints. After all, it’s already evident that an update is forthcoming with the Polish TD branch and, in early September, Czechoslovak autocannon Light tanks. Moreover, before the release of the Czech Light tanks, there will be at least one more Assembly Shop event to drain resources, as guaranteed.