Training for 3k

It's a good thing that you are preparing so far in advance. I think that you should take at least a month of steadily increasing your overall training volume, keeping the quality high. You can run a good 3k off of 75k, but I think you would have much more potential with at least 100k per week. I believe your recent 10k, in addition to your 1500 pr, indicate that you have good potential for a fast 3k or 5k. If increasing your volume seems very hard, try to run part of your runs on trails, if possible.

Personally, my go-to 3k workouts are: 3-5 kilometer repeats at 5k pace, with 2-3 minutes rest, jog ten minutes, then several 200's at mile pace. Or: 12-15x 400 at 5k pace, where every third repeat is at 3k pace. Also, I recommend picking up the pace at the end of almost every non-workout day, and including "floating" strides and short hill repeats of 50m with full recovery, at least twice a week. Long hill repeats are good too, if you want to try replacing a track workout.

Thanks for the tips, Occasionally I do pick up the pace at the end when feeling good and do some strides when i have the time. I'll try to up my mileage a bit more to around 60 miles/ a bit below 100k although it remains below of what I've found online to be optimal.

Also I purchased healthy intelligent training and Daniel's Formula to learn more.

Just looking at your interval workouts and your recent 10km race (3 mins 24 per km) I think you might be running your interval workouts too fast to be really developing your aerobic fitness. I am not sure what comeptitions you have coming up short term, but I would reduce the pace of your 1000m reps, and probably increase the number to 8 and then 10 making sure that you don't feel destroyed by the workout. Increasing your 400s up to 15 repetitions as you suggest is along the same lines but reduce the pace as well as you do this. One or 2 days a week I would add strides (say 5 to 8 x 80 to 100m) or short hills (5 to 8 x 9 seconds) to work on your speed, again don't try and kill yourself on these when you start them to keep the risk injury low. When changing your training, try to pay attention to how you feel and how your body is adjusting - those things will be good guides as to whether you are going in the right direction.

People will try to help and give you advice on these boards (bar a few trolls) as well as they can but does not Portugal have very good running coaches who can help you closer to home?

I mostly disagree on the interval workout paces being too fast. He seems more speed based and has relatively low mileage, so I don't think the 10k time is a good reference point. Really the solo 1k session is not that fast even relative to 34-low. 8-10 x1k is cool, but it's a very different workout. But yes definitely more tempos and aerobic work would help