British Orienteering has published the selection policy for 2020 internationals (News Item - Senior Selection 2020). Target races are the (Sprint) World Championships, and the three rounds of the World Cup, including the (Forest) European Championships.
Only forest performances matter for forest selections, and only sprint performances matter for sprint selections.
Perhaps particularly for the various sprint disciplines - with many strong GB athletes, little racing so far in 2018, fewer spaces at the first ever sprint only World Champs, and the new knockout sprint format fully launched - it will be interesting to see how things go. On the subject of little racing the policy notes that last weekend's British Championship Sprints (a World Ranking Event, in which Kris Jones and Megan Carter-Davies had clear wins) are out of consideration because the policy is published after the races.
On The Red Line (Update post-World Cup Round 3 in Switzerland: Kris and Megan both showed strongly with top-10s in both sprints of 2019 World Cup Round 3, so could have done enough already to be invited to go back to Switzerland for 2020 World Cup Round 1.)
In addition to results in named races there are other criteria that may be considered, perhaps most notably that of having demonstrated potential to achieve a podium at WOC. Also, for the World Cup Round 1 selection, the top-10s at WOC2018 (Latvia) are considered - Kris Jones and Alice Leake were top-10s in the Sprint.
The first round of the 2020 World Cup is in Switzerland from May 20th to 24th. There is a long distance and both types of individual sprint. The long distance is on the Thursday and the sprints (knockout first) on Saturday and Sunday.
JK Sprint Map Snippet
In 2020 the JK (the Easter weekend of 10th-13th April) is in the north-east of England, and includes three IOF World Ranking races: sprint, middle and long, and also forest relays.
All four JK races are "selection" at this stage (for World Cup 1) and later when it comes to the World Champs and European Champs.
(Two more map snippets are below.)
The team for World Cup 1 will be chosen after the JK. The JK races are selection, and from 2019 the World Champs (Norway) and the Swiss and Chinese World Cup rounds.
Others selections, for the World Championships, the European Championships, and World Cup Round 3, will be made after open test races provided in Denmark by the World Championships Organisers (these are provisionally scheduled for May 30th and 31st, the weekend after World Cup Round 1).
Only 2020 races are included - the 2019 races used to select for World Cup Round 1 are no longer in the set.
For the World Championships the races (of which there are five) are:
For the European Championships the races (of which there are six) are:
World Champs In the Sprint and Knock-Out Sprint competitions, GB may enter three women and three men, and a single sprint relay team. At this year's forest World Champs with a similar number of races GB fielded nine athletes, and it might be a similar number for the sprint world champs.
European Champs GB can have, for both men and women, six entries in the middle and three in the long, Also two relay teams for each of men and women. So the team size is likely to be at least twelve, and perhaps towards eighteen.
Sprint, Knockout Sprint and Sprint Relay, with a rest day between race days.
European Orienteering Champs: Estonia, August 19th-23rd.
Middle qualifiers, long distance, rest day, middle finals, relays.
World Cup Round 3: Italy, October 1st - 6th.
All forest - long, middle and relays.
JK Middle Distance Map Snippet
JK Long Distance Map Snippet