Puerh Tea Cake

From the Kent&Sussex Tea&Coffee Co website : Fantastic individually wrapped Chinese Tea Cake. Made from Pu erh Tea. This highly unusual tea cake is a compacted Black Tea. 5g of Black Tea enough to make a good large pot of tea. Very nice deep rich flavour.
Brewing instructions : For mini tea cake, brew for 1 min wth water of 80 degrees, these can have between 5-6 further infusions.

I bought these as my previous (and first overall) experience with mini pu erh tea cakes was very positive. I don´t know whether it´s the same tea as in my first experience (most likely not) but I encountered some differences : although the steeping is carried out with water at 80ºC for 1 minute (vs 100ºC for min. 2 minutes), the resulting tea is far darker; it´s easier to drink (smoother, less peaty), but in a way it seems more mainstream (or at least it gives that impression to me). I´ve already reused the tea cake twice (it broke completely down during the 2nd steeping session) but there´s still no need to change steeping time as the resulting brew is still very dark and hasn´t changed its intensity yet. Tomorrow I´ll be reusing the tea cake even more…

So, resuming this experience for now (for reasons of comparison, I´ve indicated the conditions of my previous experience as well) : I heated water to 100ºC and had it cool down to 80ºC, before pouring it on the mini tea cake (last time, I used the freshly boiled water to give the mini cake a quick rinse of 10s max. and immediately poured new boiling water on the mini cake which I then steeped for 2 minutes). I used a ceramic mug with a (ceramic) tea filter which can easily be taken out, so I just withdrew the filter and the loosened cake in the filter was immediately ready for a second brew. About an hour later I steeped the pu erh a second time, by pouring freshly boiled + cooled down to 80ºC water over the tea filter in the mug. I steeped it again for 1 minute (last time I used freshly boiled water and had it steep for 2.5 minutes) and the colour of the tea was similar to the first brew. Not a lot of change in taste and smell either. This applies equally for 3rd brew (last time I added 30s of steeping time with every reuse of the mini cake, but the colour went down from the 3rd brew onwards, and the 5th brew was clearly inferior, with almost no colour developping).