Last week I was metaphorically nudged in the ribs by a reader and concert-goer, one of the diehards who goes to just about everything.

"Isn't it a shame about Weller and Lazarev," he said. "What do you mean?" I asked. "Neither of them was here this season and now we know that neither of them will be here next season. Have they been ditched?"

He was referring to two of the RSNO's house team of conductors, both titled Conductor Emeritus: the Viennese Walter Weller and the Russian Alexander Lazarev. Interestingly, it's not long since one of the musicians privately made a similar observation. Weller and Lazarev are both former principal conductors of the RSNO, since when they have been regular guest conductors, both with a great deal to say in their fields, and each of them with a distinctive and highly individual way of saying it.

Personally, I wouldn't read too much yet into their absence from the schedules. The orchestra is bang in the middle of a huge change in its administration, with new artistic staff to the left and right of the platform. The last year has been a build-up to the forthcoming departure of Stephane Deneve and the imminent arrival of conductor Peter Oundjian, Deneve's successor as music director. Added to that is the establishment of two permanent leaders of the orchestra, the appointments of a new principal second violin and principal cello, with a new principal viola and principal trumpet to follow.

Then off the stage we have a new chief executive who, without yet dotting the i's and crossing the t's, has already made it plain that extensive change "at some pace" is on the way, change which will redefine where the orchestra goes, where it plays, what it plays, and to whom it does the playing.

Meanwhile, Oundjian is just about in the door and, with his first full season now unveiled, there is a very literal interpretation we can draw from what we know. Oundjian and his team, consisting of principal guest conductor Thomas Sondergard and assistant conductor Christian Kluxen, will, between them, take 13 of the programmes. That's more than half the season. Add in the big-name regular guests, Sir Andrew Davis and Conductor Laureate Neeme Jarvi, and the schedules are already under pressure. Factor in the vital new blood – a handful of new conductors – and you're already having to sit some potential candidates on the bench. Ergo, perhaps, no Walter Weller and no Alexander Lazarev.

Maybe I'm being too kind. Maybe there are other interpretations. It's possible Oundjian wants to clear the ground and recruit fresh blood, his own hand-picked team of guest conductors. Name me a single new broom who doesn't want to do a bit of sweeping and re-fashion his new outfit to his own design. Maybe Oundjian is not interested in the old guard. We don't know and we can't guess. We'll just have to wait and see what happens beyond next season.

If it is the case that we are witnessing the beginning of the end for Lazarev and Weller, then that would be a shame. These are big guys. Lazarev mellowed incredibly from his earliest days when he visited Glasgow with the Bolshoi Opera, of which he was then the boss. Meeting him then and attempting to interview him was like talking to a rock. You could never have guessed at the wicked humourist and rather buccaneering character that would emerge a decade later. And he always put on a good show.

Weller, an unshakeable traditionalist, came out of the very roots of the Austro-German tradition. Many (including me in my early days) shrank from his conservatism. But as we came to learn, for reasons we could never logically explain, when Weller stood in front of the RSNO with a programme from that tradition – Beethoven, Bruckner, Mahler or whoever – the orchestra changed, in its sound, its weight, its depth and its authority. It was utterly compelling and authentic. Surely these people and what they can do will not be allowed to drift into neglect?