A bit of explanation . Under s9 of the Sexual Offences Act 2003 intercourse with a girl under of 15 is punishable by a maximum of 14 years imprisonment. Under the old law (1956), amazingly, it was only punishable with two years. The offence is now described as sexual activity with a child. Whether the defendant is a teacher or not is entirely irrelevant
What svejk appears to be referring to, about it only being an offence for teachers since 2001 (in fact 2003), is sexual activity with a child by a person in a position of trust, contrary to s16 of the same Act. The section applies to a wide range of people in such a position and places, from hospitals to care homes and, of course, schools. It applies to sexual activity in the form of intentional touching but the maximum penalty is 5 years. If the activity is intercourse the section is not applicable and the offence is charged as the offence, applicable to anybody whether in a position of trust or not, with the higher maximum.