How to work with upcoming events without year

I have a React native application with events where I have event dates in ISO format. I need to work with events on a yearly repeating basis. Events include dates like birthdays and also yearly events. I need to display upcoming events for the rest of the current year then display events for the next year. How to work with events without a year and sort by current date?

events.sort((a, b) => {
    const today = new Date();
    const currentYear = today.getFullYear();
    const dateA = new Date(a.date);
    dateA.setFullYear(currentYear);
    const dateB = new Date(b.date);
    dateB.setFullYear(currentYear);
    return dateA - dateB;
})
.filter(event => {
    const today = new Date();
    const currentYear = today.getFullYear();
    const eventDate = new Date(event.date);
    eventDate.setFullYear(currentYear);
    return eventDate > today;
})
.splice(0, 5)
.map(event => {
...