I was wondering how useful your schools' marking policy was to you as a teacher and, of course, to your pupils.
Marking policies are there to help teachers have a common framework by which they can regularly assess their pupils; this is useful enough and many have a timeframe attached. For example, they may state that marking must be carried out every three weeks.
Clearly, the idea is that pupils need regular feedback on their written work and this is often interpreted by time-pressured teachers who quickly tick through notes and add depth to one 'substantial' piece of writing. This is an example of an asynchronous process and, in my opinion, it is not particularly helpful for pupils or teachers!
The depth of the feedback offered can be as detailed as anyone may ask: literacy/numeracy comments, next steps, grades or levels, literacy/numeracy levels and feedback by pupils. The best assessment, however, is not driven by imposed windows of time.