I search for the bit where the Pa Auk Sayadaw mentions one can skip jhana levels but I can't seem to find it. Sorry I'm really bad at finding section from texts. Can you help? All I find are that you can skip jhana into vipassana but I can't find the skipping from access concentration to the various jhana levels.
I thought he discussed this in the context of supernormal powers in "Knowing and Seeing" (PDF on Buddhanet.net), but I see he just mentions supernormal powers and that they require mastery of jhanas in fourteen ways:
Psychic powers (abhinnà-nisaÿsa): If one wants to master the mundane psychic powers, like the recollection of past lives (pubbenivàsànussati-abhinnaà), the divine eye (dibbacakkhu), the divine ear (dibba-sota), knowing the mind of others (paracitta-vijànana), and the supernormal powers (iddhividha), flying, walking on water, etc., one must develop the ten kasinas and eight attainments (samàpatti) in fourteen ways. This is the third benefit of concentration.
This is described in detail in Visuddhimagga, Chapter XII, paragraph 2.
He must have complete control of his mind in the following ways: (i) in the order of the kasinas, (ii) in the reverse order of the kasinas ... (vi) skipping jhanas, (viii) skipping kasinas, ...
5. (vii) He skips alternate jhanas without skipping the kasinas in the following way: having first attained the first jhana in the earth kasina, he attains the third jhana in that same kasina, ...
I see that Pa Auk Sayadaw (in "Knowing and Seeing") talks about changing to different jhanas by coming out of jhana then going back into a different jhana, rather than transitioning between jhanas, as Shaila describes.
Anyway, as I said, I'm not an expert on this, just offering what I've read in various places.