@benn there is not way to predict which devices will be loosing support first. It will all depend on the device manufacturers and number of users using it. You can see the list of devices requested for /e/ to support here [POLL] Which device(s) you would like /e/ to support next? on this list some devices have been requested multiple times by different users. They get preference for support. Others are not so popular and some are not even available for purchase anymore in the market. You should choose a model which supports Oreo and Pie for now. Then check if it is supported by Lineage. Then the chances of long term support are brighter. Long term in smart phones is a very short duration i guess 1- 2 years at most very rarely do people carry phones beyond that . Though I have a ten year old nokia 6030 which work perfectly even today!